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This is a picture of an opening in the 2015 A8 Torque Converter. Presumably it is there for inspection of the converter.
The opening should be covered by this rubber plug part number 12551987.
The opening is only a foot or so from the tunnel so it catches all the heat generated by the crossover pipe in the tunnel, the exhaust pipes exiting the tunnel and any debris picked up and catapulted rearward. After a couple of track days this is what the plug looks like.
As you can see it is starting to melt and if you could see it from the side it has been pushed in slightly. After another track day or two it will melt and fail completely and debris will go directly into the torque converter housing.
I had the exhaust pipes wrapped up to the tunnel plate and after seeing this I removed the plate and wrapped the pipe to the crossover.
So my question is, has anybody else seen this kind of damage to the plug and what did you do about it? Is there an aftermarket source for a metal plug that will not melt?
OP, thank you for raising the flag. I am not sure anyone has checked for this before. Will you be able to write a short instruction for how to check for the melted plug? I am sure A6 and A8 owners will be interested.
Not sure this is the answer you were looking for but I think you will need to put the car on a lift or on jack stands and crawl under it to look. I just tried to reach it from laying on the floor beside the car and by placing a mirror as far under the car as I could. Both those methods proved futile. I have a lift and that is how I found it. I could be wrong but I do not think that it Will melt in normal driving...only track duty...but I could be wrong. As you can see from the picture, it is located above the exhaust pipes as they split around the transmission. It should be in the same location on the A6.
When I originally started this thread it was to point out that if the rubber plug that covers the access hole to the Torque Converter gets damaged from heat, melts and falls off there is potential to get debris into the torque converter. Apparently that is what happened to the seal on my torque converter. On my last track day at VIR with the NCM my transmission began leaking fluid. The technician at my local dealer feels that by the time I discovered the plug was missing (after my first 3 track days) there was already debris in the seal and that is what is causing the transmission to leak fluid. He is now dropping the rear carriage out of the car to replace the Torque Converter Seal.
I doubt it although I have not gotten under a c7 A6 to verify I would not think that the design of the torque converter changed. Although I cannot verify it, I suspect the culprit is putting the exhaust inside the tunnel that has created the heat since it is directly in front of the rubber boot on the converter and I think that change was for the A6 as well.
Before 2 days at VIR I tried to fix the problem of the plug melting and disappearing. I put duct tape over the plug and then put 2000 degree thermo tape over that. Here is what it looked like:
Here is what it looked like after:
You can also notice that I wrapped the x-pipe with header wrap also and even that did not help. On the 2016 X-pipe there is an additional raised shield welded onto the pipe. Does this solve the issue??? no idea.
Obviously this situation was overlooked by GM designers.
A metal fabricator could use a new plug as a template & fashion a cover from metal. Maybe w/ vent holes providing some ventilation?
It's obvious one has to do something because this is not good, debris getting sucked in will wipeout tranny in short order.
Kicker's a new tranny would STILL come w/ same rubber/ized cover, too.
Well, I guess that's my fault to not have payed attention that Car54 was on both post...
My first plug lasted 4 track day week end. I was not pushing the car much. The second one lasted 4 sessions in 80F temps before being swallowed....
I have some plastic grind coming out of the transmission weeping hole due to the plug being destroy inside the bell housing. Hopefully the metal shield in front of the plug will be the fix for track days.
What steps I should take from there to reduce/avoid transmission and torque converter damage ? Transmission triple flush and replace filter ? Redo the seal between the transmission and the bell housing ?
what are your experiences ?
I will see if I can find the ticket from the dealer when I took mine in for service the first time it melted. There was some evidence of fluid leakage but not much. It may take me awhile to find it.
Sorry I am so late in responding. Things just got really busy. The short answer is that I could not find the ticket from the dealer where he replaced the plug the first time. As I said there was evidence of fluid but I am sure he did not replace the torque converter nor did he flush the transmission as I recall. I am just not sure exactly what he did.
05-19-2016, 04:24 PM
Melted plug on Torque Converter
